65
9-7-3. Outdoor power circuit board
MXZ-8A140VA
CNAF
Connect to
ACTM
SC-P2, SC-N2
Connect to
ACTM and the
soothing
capacitor
SC-P1
Connect to 52C
SC-N1
Connect to ACTM
–
+
}
Brief Check of POWER MODULE
W
Usually, they are in a state of being short-circuited if they are broken.
Measure the resistance in the following points (connectors, etc.).
If they are short-circuited, it means that they are broken.
1. Check of POWER MODULE
1
.Check of DIODE circuit
L - P1 , N - P1 , L - N1 , N - N1
2
.Check of IGBT circuit
P2 - U , P2 - V , P2 - W , N2 - U , N2 - V , N2 - W
Note:The marks, L , N , N1 , N2 , P1 , P2 , U , V and W
shown in the diagram are not actually printed on the board.
POWER
MODULE
CNDC
280V-350V DC
Connect to the outdoor controller
circuit board (CNDC)
P1
P2
N1
L
N
N2
U
V
W
CN5
Detection of
primary current
(Connect to the
outdoor noise filter
circuit board (CN5))
CN3
Temperature
<Heatsink>
(TH8)
CN4
Connect to the
outdoor controller
circuit board
(CN4)
TAB-U, TAB-V,
TAB-W
Connect to the
compressor (MC)
Voltage among
phases:
5V-180V AC
SC-R, SC-S
Connect to the
outdoor noise filter
circuit board
(LO, NO)
220V-240V AC
CN2
Connect to the outdoor controller circuit
board (CN2)
1
-
5
: Power circuit board
➔
Transmitting
signal to the controller board (0-5V DC)
2
-
5
: Zero cross signal (0-5V DC)
3
-
4
: 18V DC
6
-
5
: 15V DC
7
-
5
: 15V DC
[
5
: –
1
,
2
,
6
,
7
: + ]
[
4
: –
3
: + ]
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